Returns a Boolean value that indicates whether a given object is present in the set.
Original signature is '- (BOOL)containsObject:(id)anObject'
Available in Mac OS X v10.0 and later.


- anObject (Id)
- The object for which to test membership of the set.

YES if anObject is present in the set, otherwise NO.

- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)